Add Qt4 windowport

Originally by Ray Chason for 3.4.3, based on the Qt windowport by
Warwick Allison. The look and feel is mostly the same.

Some improvements over the Qt 3 interface are:

* Panes are resizable
* Full support for IBMgraphics, and walls and corridors are drawn with
  graphical primitives for a continuous appearance no matter what the font
  says
* Lots of irritating glitches fixed
* Menus support proportional fonts correctly

Adding this because the old Qt windowport cannot be compiled on Qt4,
even with Qt3 compatibility stuff.

TODO:
 - background map glyphs
 - status hilites
 - menucolors

win/Qt4/qt4key.cpp

@@ -0,0 +1,91 @@
+// Copyright (c) Warwick Allison, 1999.
+// Qt4 conversion copyright (c) Ray Chason, 2012-2014.
+// NetHack may be freely redistributed.  See license for details.
+
+// qt4key.cpp -- a key buffer
+
+#include "hack.h"
+#undef Invisible
+#undef Warning
+#undef index
+#undef msleep
+#undef rindex
+#undef wizard
+#undef yn
+#undef min
+#undef max
+
+#include <QtGui/QtGui>
+#include "qt4key.h"
+
+namespace nethack_qt4 {
+
+NetHackQtKeyBuffer::NetHackQtKeyBuffer() :
+    in(0), out(0)
+{
+}
+
+bool NetHackQtKeyBuffer::Empty() const { return in==out; }
+bool NetHackQtKeyBuffer::Full() const { return (in+1)%maxkey==out; }
+
+void NetHackQtKeyBuffer::Put(int k, int a, int state)
+{
+    if ( Full() ) return;	// Safety
+    key[in]=k;
+    ascii[in]=a;
+    in=(in+1)%maxkey;
+}
+
+void NetHackQtKeyBuffer::Put(char a)
+{
+    Put(0,a,0);
+}
+
+void NetHackQtKeyBuffer::Put(const char* str)
+{
+    while (*str) Put(*str++);
+}
+
+int NetHackQtKeyBuffer::GetKey()
+{
+    if ( Empty() ) return 0;
+    int r=TopKey();
+    out=(out+1)%maxkey;
+    return r;
+}
+
+int NetHackQtKeyBuffer::GetAscii()
+{
+    if ( Empty() ) return 0; // Safety
+    int r=TopAscii();
+    out=(out+1)%maxkey;
+    return r;
+}
+
+Qt::KeyboardModifiers NetHackQtKeyBuffer::GetState()
+{
+    if ( Empty() ) return 0;
+    Qt::KeyboardModifiers r=TopState();
+    out=(out+1)%maxkey;
+    return r;
+}
+
+int NetHackQtKeyBuffer::TopKey() const
+{
+    if ( Empty() ) return 0;
+    return key[out];
+}
+
+int NetHackQtKeyBuffer::TopAscii() const
+{
+    if ( Empty() ) return 0;
+    return ascii[out];
+}
+
+Qt::KeyboardModifiers NetHackQtKeyBuffer::TopState() const
+{
+    if ( Empty() ) return 0;
+    return state[out];
+}
+
+} // namespace nethack_qt4